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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0440 PM CDT Fri Sep 19 2025 Valid 211200Z - 271200Z ...Day 3/Sunday... A mid-level trough and attendant surface cold front will move through the Pacific Northwest bringing wetting rains west of the Cascades. Increasing cloud cover as well as rising relative humidity will be counteracted with stronger onshore flow and downslope westerly winds on the lee of the Cascades and portions of the Columbia Basin Day 3/Sunday. The very dry conditions Saturday will maintain existing dry fuels across the region, with 40% critical probabilities maintained for portions of the Columbia Basin. Residual sub-tropical moisture, daytime instability and topographic forcing will support another day of isolated to widely scattered thunderstorms across much of the Intermountain West on Day 3/Sunday. More diffuse moisture will be in place overall, leading to some dry lightning strikes outside wetting rain cores. However, fuels remain only marginally receptive to ignition with widespread new lightning starts not expected. ...Days 4-6/Monday-Wednesday... Surface high pressure settling into the northern Rockies along with a developing coastal trough will support weak easterly offshore flow across the Cascades Day 5/Tuesday, potentially extending into Day 6/Wednesday. Lower daytime relative humidity as well as poor overnight recoveries could impact existing fires but the relatively light east winds as well as preceding precipitation this weekend should attenuate a significant fire weather threat. A mid-level troughing pattern evolving across the eastern CONUS next week will promote widespread wetting rains across the Midwest, Ohio River Valley and Appalachians, where fuels have been persistently dry. This should reduce the fire weather threat across the region with the exception of the Deep South, where limited rainfall could sustain very dry fuels. ...Days 7-8/Thursday-Friday... An increase in forecast uncertainty in the evolution of upper-level flow pattern exists in the long term. A potential trough/low could bring additional rain into the southern California and the Desert Southwest by the end of next week while a general warming and drying trend becomes established across the Northern Rockies and Pacific Northwest. However, fuel conditions are expected to remain rather benign in terms of supporting wildfire spread in the long term. ..Williams.. 09/19/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0440 PM CDT Fri Sep 19 2025 Valid 211200Z - 271200Z ...Day 3/Sunday... A mid-level trough and attendant surface cold front will move through the Pacific Northwest bringing wetting rains west of the Cascades. Increasing cloud cover as well as rising relative humidity will be counteracted with stronger onshore flow and downslope westerly winds on the lee of the Cascades and portions of the Columbia Basin Day 3/Sunday. The very dry conditions Saturday will maintain existing dry fuels across the region, with 40% critical probabilities maintained for portions of the Columbia Basin. Residual sub-tropical moisture, daytime instability and topographic forcing will support another day of isolated to widely scattered thunderstorms across much of the Intermountain West on Day 3/Sunday. More diffuse moisture will be in place overall, leading to some dry lightning strikes outside wetting rain cores. However, fuels remain only marginally receptive to ignition with widespread new lightning starts not expected. ...Days 4-6/Monday-Wednesday... Surface high pressure settling into the northern Rockies along with a developing coastal trough will support weak easterly offshore flow across the Cascades Day 5/Tuesday, potentially extending into Day 6/Wednesday. Lower daytime relative humidity as well as poor overnight recoveries could impact existing fires but the relatively light east winds as well as preceding precipitation this weekend should attenuate a significant fire weather threat. A mid-level troughing pattern evolving across the eastern CONUS next week will promote widespread wetting rains across the Midwest, Ohio River Valley and Appalachians, where fuels have been persistently dry. This should reduce the fire weather threat across the region with the exception of the Deep South, where limited rainfall could sustain very dry fuels. ...Days 7-8/Thursday-Friday... An increase in forecast uncertainty in the evolution of upper-level flow pattern exists in the long term. A potential trough/low could bring additional rain into the southern California and the Desert Southwest by the end of next week while a general warming and drying trend becomes established across the Northern Rockies and Pacific Northwest. However, fuel conditions are expected to remain rather benign in terms of supporting wildfire spread in the long term. ..Williams.. 09/19/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

5-Day Uncertainty Track last updated Fri, 19 Sep 2025 20:45:09 GMT


Wind Speed Probabilities last updated Fri, 19 Sep 2025 21:21:32 GMT

Issued at 500 PM AST Fri Sep 19 2025 656 WTNT42 KNHC 192041 TCDAT2 Tropical Storm Gabrielle Discussion Number 11 NWS National Hurricane Center Miami FL AL072025 500 PM AST Fri Sep 19 2025 Gabrielle's cloud pattern has changed significantly since the last advisory. The previously noted shear pattern has changed to a curved convective band pattern, and the previously exposed low-level center has become at least partly covered by cirrus clouds spreading westward from the convection. This change suggests that the storm is starting to encounter the forecast decrease in vertical shear. At this time, this change has not led to an increase in the various satellite intensity estimates, so the initial intensity remains 45 kt. The initial motion is 300/10 kt. Gabrielle is on the southwest side of the subtropical ridge, and during the next 2-3 days it is expected to turn northward between the ridge to the east and and a mid-latitude trough over the eastern United States and the far western Atlantic. The track guidance remains fairly tightly clustered during this time, although the consensus models have shifted a little to the left since the last advisory. This part of the new forecast track is nudged a little to the left, but still lies east of the consensus models. After 3 days, Gabrielle is expected to recurve into the westerlies and accelerate northeastward. The guidance shows more spread during this time, with the GFS being to the left/north and faster than most of the guidance, while the ECMWF is to the right/south and slower. Despite the spread, the consensus models and the center of the guidance envelope are have changed little since the last advisory for this part of the forecast. Thus, the new forecast is similar to, but slightly slower than, the previous forecast. The reliable track models still show Gabrielle's center passing at least 130 n mi east of Bermuda in 60-72 h. However, interests on the island should continue to monitor Gabrielle's progress since NHC's average track error at 72 h is about 90 n mi, and hazards can extend well away from the center. There remains a 20-25 percent chance of tropical-storm-force winds occurring on Bermuda. Gabrielle is now forecast to be in a light-to-moderate shear environment for the next 72 h, which should allow strengthening that would be tempered mainly by occasional entrainment of dry air. The new intensity forecast has been tweaked a bit to show a peak intensity of 90 kt at 72 h. Extratropical transition should be underway by 120 h, and could be complete by that time if the cyclone takes a more northward track similar to the GFS. However, a more southward track similar to the ECMWF would delay transition, and based on the uncertainty the new intensity forecast keeps the system as a tropical cyclone at 120 h. KEY MESSAGES: 1. Gabrielle is forecast to become a hurricane by Sunday and pass east of Bermuda Sunday night and Monday. Interests on Bermuda should monitor Gabrielle's forecasts since it is too soon to specify the magnitude of potential wind and rainfall impacts. 2. Swells generated by Gabrielle are expected to reach Bermuda tonight and build through the weekend. These swells are likely to cause life-threatening surf and rip current conditions. FORECAST POSITIONS AND MAX WINDS INIT 19/2100Z 22.4N 56.6W 45 KT 50 MPH 12H 20/0600Z 23.5N 58.0W 45 KT 50 MPH 24H 20/1800Z 25.0N 59.4W 55 KT 65 MPH 36H 21/0600Z 26.8N 60.6W 65 KT 75 MPH 48H 21/1800Z 28.6N 61.4W 75 KT 85 MPH 60H 22/0600Z 30.6N 61.6W 85 KT 100 MPH 72H 22/1800Z 33.0N 59.9W 90 KT 105 MPH 96H 23/1800Z 38.1N 51.3W 90 KT 105 MPH 120H 24/1800Z 42.1N 38.4W 70 KT 80 MPH $$ Forecaster Beven

Issued at 2100 UTC FRI SEP 19 2025 000 FONT12 KNHC 192041 PWSAT2 TROPICAL STORM GABRIELLE WIND SPEED PROBABILITIES NUMBER 11 NWS NATIONAL HURRICANE CENTER MIAMI FL AL072025 2100 UTC FRI SEP 19 2025 AT 2100Z THE CENTER OF TROPICAL STORM GABRIELLE WAS LOCATED NEAR LATITUDE 22.4 NORTH...LONGITUDE 56.6 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 45 KTS...50 MPH...85 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) ATLANTIC STANDARD TIME (AST)...SUBTRACT 4 HOURS FROM Z TIME EASTERN DAYLIGHT TIME (EDT)...SUBTRACT 4 HOURS FROM Z TIME CENTRAL DAYLIGHT TIME (CDT)...SUBTRACT 5 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 18Z FRI AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 18Z FRI 06Z SAT 18Z SAT 06Z SUN 18Z SUN 18Z MON 18Z TUE PERIODS TO TO TO TO TO TO TO 06Z SAT 18Z SAT 06Z SUN 18Z SUN 18Z MON 18Z TUE 18Z WED FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT SANTA CRUZ AZO 34 X X( X) X( X) X( X) X( X) X( X) 6( 6) BERMUDA 34 X X( X) X( X) 4( 4) 22(26) X(26) X(26) BERMUDA 50 X X( X) X( X) X( X) 4( 4) X( 4) X( 4) BERMUDA 64 X X( X) X( X) X( X) 1( 1) X( 1) X( 1) $$ FORECASTER BEVEN

Issued at 2100 UTC FRI SEP 19 2025 000 WTNT22 KNHC 192040 TCMAT2 TROPICAL STORM GABRIELLE FORECAST/ADVISORY NUMBER 11 NWS NATIONAL HURRICANE CENTER MIAMI FL AL072025 2100 UTC FRI SEP 19 2025 TROPICAL STORM CENTER LOCATED NEAR 22.4N 56.6W AT 19/2100Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 300 DEGREES AT 10 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1004 MB MAX SUSTAINED WINDS 45 KT WITH GUSTS TO 55 KT. 34 KT.......130NE 100SE 0SW 70NW. 4 M SEAS....300NE 180SE 90SW 210NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 22.4N 56.6W AT 19/2100Z AT 19/1800Z CENTER WAS LOCATED NEAR 22.1N 56.1W FORECAST VALID 20/0600Z 23.5N 58.0W MAX WIND 45 KT...GUSTS 55 KT. 34 KT...120NE 90SE 0SW 70NW. FORECAST VALID 20/1800Z 25.0N 59.4W MAX WIND 55 KT...GUSTS 65 KT. 50 KT... 30NE 20SE 0SW 20NW. 34 KT...120NE 90SE 30SW 70NW. FORECAST VALID 21/0600Z 26.8N 60.6W MAX WIND 65 KT...GUSTS 80 KT. 64 KT... 15NE 0SE 0SW 0NW. 50 KT... 30NE 20SE 10SW 20NW. 34 KT...130NE 100SE 30SW 80NW. FORECAST VALID 21/1800Z 28.6N 61.4W MAX WIND 75 KT...GUSTS 90 KT. 64 KT... 20NE 15SE 10SW 15NW. 50 KT... 35NE 30SE 15SW 25NW. 34 KT...140NE 110SE 40SW 80NW. FORECAST VALID 22/0600Z 30.6N 61.6W MAX WIND 85 KT...GUSTS 105 KT. 64 KT... 25NE 20SE 10SW 15NW. 50 KT... 40NE 40SE 20SW 30NW. 34 KT...150NE 140SE 50SW 90NW. FORECAST VALID 22/1800Z 33.0N 59.9W MAX WIND 90 KT...GUSTS 110 KT. 64 KT... 30NE 30SE 20SW 20NW. 50 KT... 50NE 50SE 40SW 40NW. 34 KT...150NE 150SE 80SW 90NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 125 NM ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 23/1800Z 38.1N 51.3W MAX WIND 90 KT...GUSTS 110 KT. 50 KT... 70NE 90SE 60SW 50NW. 34 KT...170NE 190SE 140SW 100NW. OUTLOOK VALID 24/1800Z 42.1N 38.4W MAX WIND 70 KT...GUSTS 85 KT. 50 KT...100NE 120SE 100SW 60NW. 34 KT...230NE 250SE 220SW 150NW. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 22.4N 56.6W NEXT ADVISORY AT 20/0300Z $$ FORECASTER BEVEN

Issued at 500 PM AST Fri Sep 19 2025 000 WTNT32 KNHC 192040 TCPAT2 BULLETIN Tropical Storm Gabrielle Advisory Number 11 NWS National Hurricane Center Miami FL AL072025 500 PM AST Fri Sep 19 2025 ...GABRIELLE STARTING TO GET BETTER ORGANIZED... ...FORECAST TO STRENGTHEN AND BECOME A HURRICANE BY SUNDAY... SUMMARY OF 500 PM AST...2100 UTC...INFORMATION ---------------------------------------------- LOCATION...22.4N 56.6W ABOUT 510 MI...820 KM NE OF THE NORTHERN LEEWARD ISLANDS ABOUT 850 MI...1365 KM SE OF BERMUDA MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H PRESENT MOVEMENT...WNW OR 300 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...1004 MB...29.65 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. Interests in Bermuda should monitor the progress of Gabrielle. DISCUSSION AND OUTLOOK ---------------------- At 500 PM AST (2100 UTC), the center of Tropical Storm Gabrielle was located near latitude 22.4 North, longitude 56.6 West. Gabrielle is moving toward the west-northwest near 12 mph (19 km/h), and a general northwestward motion is expected through Saturday. A gradual turn towards the north-northwestward is expected by Saturday night, followed by a northward motion by Sunday night. On the forecast track, the center of Gabrielle is expected to pass east of Bermuda Sunday night and Monday. Maximum sustained winds are near 50 mph (85 km/h) with higher gusts. Gradual strengthening is forecast, and Gabrielle is expected to become a hurricane by Sunday. Tropical-storm-force winds extend outward up to 150 miles (240 km) from the center. The estimated minimum central pressure is 1004 mb (29.65 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Gabrielle can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT2 and WMO header WTNT42 KNHC. SURF: Swells generated by Gabrielle are expected to reach Bermuda tonight and build through the weekend. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next complete advisory at 1100 PM AST. $$ Forecaster Beven

...GABRIELLE STARTING TO GET BETTER ORGANIZED... ...FORECAST TO STRENGTHEN AND BECOME A HURRICANE BY SUNDAY... As of 5:00 PM AST Fri Sep 19 the center of Gabrielle was located near 22.4, -56.6 with movement WNW at 12 mph. The minimum central pressure was 1004 mb with maximum sustained winds of about 50 mph.

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...Columbia Basin... Increasing west/southwest flow aloft ahead of the next Pacific Northwest mid-level trough as well as an increasing onshore pressure gradient will promote enhanced downslope winds leeward of the Cascades and into the Columbia Basin Saturday. Breezy winds of 10-15 mph (localized Cascade gap winds of 20 mph) and relative humidity as low as 10% amid dry fuels will support an elevated fire weather threat for the Columbia Basin. No significant changes were made to the existing Elevated highlight area. ..Williams.. 09/19/2025 .PREV DISCUSSION... /ISSUED 0127 AM CDT Fri Sep 19 2025/ ...Synopsis... Elevated fire-weather conditions are forecast across portions of the northern Cascades as a mid-level trough approaches the Pacific Northwest. Otherwise, generally weak surface winds across the U.S. and higher precipitable water content where convection is expected will diminish any widespread fire-weather concerns. ...Northern Cascades... Ridging and an intensifying height gradient aloft from an approaching mid-level trough will result in some downslope westerly surface winds through the Cascade gaps. These winds are expected to reach 15-20 MPH, with relative humidity values as low as 10-15%. With ERCs hovering around the 80th annual percentile, and some additional curing of fuels expected on Friday, at least Elevated fire-weather highlights are warranted at this time. ...Southern Cascades... Some potential for thunderstorm activity exists Saturday evening across portions of the Oregon Cascades. However, precipitable water content at or exceeding 1 inch, slow storm motions, low buoyancy, and meager fuels will limit the overall threat of lightning-based ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...Columbia Basin... Increasing west/southwest flow aloft ahead of the next Pacific Northwest mid-level trough as well as an increasing onshore pressure gradient will promote enhanced downslope winds leeward of the Cascades and into the Columbia Basin Saturday. Breezy winds of 10-15 mph (localized Cascade gap winds of 20 mph) and relative humidity as low as 10% amid dry fuels will support an elevated fire weather threat for the Columbia Basin. No significant changes were made to the existing Elevated highlight area. ..Williams.. 09/19/2025 .PREV DISCUSSION... /ISSUED 0127 AM CDT Fri Sep 19 2025/ ...Synopsis... Elevated fire-weather conditions are forecast across portions of the northern Cascades as a mid-level trough approaches the Pacific Northwest. Otherwise, generally weak surface winds across the U.S. and higher precipitable water content where convection is expected will diminish any widespread fire-weather concerns. ...Northern Cascades... Ridging and an intensifying height gradient aloft from an approaching mid-level trough will result in some downslope westerly surface winds through the Cascade gaps. These winds are expected to reach 15-20 MPH, with relative humidity values as low as 10-15%. With ERCs hovering around the 80th annual percentile, and some additional curing of fuels expected on Friday, at least Elevated fire-weather highlights are warranted at this time. ...Southern Cascades... Some potential for thunderstorm activity exists Saturday evening across portions of the Oregon Cascades. However, precipitable water content at or exceeding 1 inch, slow storm motions, low buoyancy, and meager fuels will limit the overall threat of lightning-based ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...Columbia Basin... Increasing west/southwest flow aloft ahead of the next Pacific Northwest mid-level trough as well as an increasing onshore pressure gradient will promote enhanced downslope winds leeward of the Cascades and into the Columbia Basin Saturday. Breezy winds of 10-15 mph (localized Cascade gap winds of 20 mph) and relative humidity as low as 10% amid dry fuels will support an elevated fire weather threat for the Columbia Basin. No significant changes were made to the existing Elevated highlight area. ..Williams.. 09/19/2025 .PREV DISCUSSION... /ISSUED 0127 AM CDT Fri Sep 19 2025/ ...Synopsis... Elevated fire-weather conditions are forecast across portions of the northern Cascades as a mid-level trough approaches the Pacific Northwest. Otherwise, generally weak surface winds across the U.S. and higher precipitable water content where convection is expected will diminish any widespread fire-weather concerns. ...Northern Cascades... Ridging and an intensifying height gradient aloft from an approaching mid-level trough will result in some downslope westerly surface winds through the Cascade gaps. These winds are expected to reach 15-20 MPH, with relative humidity values as low as 10-15%. With ERCs hovering around the 80th annual percentile, and some additional curing of fuels expected on Friday, at least Elevated fire-weather highlights are warranted at this time. ...Southern Cascades... Some potential for thunderstorm activity exists Saturday evening across portions of the Oregon Cascades. However, precipitable water content at or exceeding 1 inch, slow storm motions, low buoyancy, and meager fuels will limit the overall threat of lightning-based ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...Columbia Basin... Increasing west/southwest flow aloft ahead of the next Pacific Northwest mid-level trough as well as an increasing onshore pressure gradient will promote enhanced downslope winds leeward of the Cascades and into the Columbia Basin Saturday. Breezy winds of 10-15 mph (localized Cascade gap winds of 20 mph) and relative humidity as low as 10% amid dry fuels will support an elevated fire weather threat for the Columbia Basin. No significant changes were made to the existing Elevated highlight area. ..Williams.. 09/19/2025 .PREV DISCUSSION... /ISSUED 0127 AM CDT Fri Sep 19 2025/ ...Synopsis... Elevated fire-weather conditions are forecast across portions of the northern Cascades as a mid-level trough approaches the Pacific Northwest. Otherwise, generally weak surface winds across the U.S. and higher precipitable water content where convection is expected will diminish any widespread fire-weather concerns. ...Northern Cascades... Ridging and an intensifying height gradient aloft from an approaching mid-level trough will result in some downslope westerly surface winds through the Cascade gaps. These winds are expected to reach 15-20 MPH, with relative humidity values as low as 10-15%. With ERCs hovering around the 80th annual percentile, and some additional curing of fuels expected on Friday, at least Elevated fire-weather highlights are warranted at this time. ...Southern Cascades... Some potential for thunderstorm activity exists Saturday evening across portions of the Oregon Cascades. However, precipitable water content at or exceeding 1 inch, slow storm motions, low buoyancy, and meager fuels will limit the overall threat of lightning-based ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...Columbia Basin... Increasing west/southwest flow aloft ahead of the next Pacific Northwest mid-level trough as well as an increasing onshore pressure gradient will promote enhanced downslope winds leeward of the Cascades and into the Columbia Basin Saturday. Breezy winds of 10-15 mph (localized Cascade gap winds of 20 mph) and relative humidity as low as 10% amid dry fuels will support an elevated fire weather threat for the Columbia Basin. No significant changes were made to the existing Elevated highlight area. ..Williams.. 09/19/2025 .PREV DISCUSSION... /ISSUED 0127 AM CDT Fri Sep 19 2025/ ...Synopsis... Elevated fire-weather conditions are forecast across portions of the northern Cascades as a mid-level trough approaches the Pacific Northwest. Otherwise, generally weak surface winds across the U.S. and higher precipitable water content where convection is expected will diminish any widespread fire-weather concerns. ...Northern Cascades... Ridging and an intensifying height gradient aloft from an approaching mid-level trough will result in some downslope westerly surface winds through the Cascade gaps. These winds are expected to reach 15-20 MPH, with relative humidity values as low as 10-15%. With ERCs hovering around the 80th annual percentile, and some additional curing of fuels expected on Friday, at least Elevated fire-weather highlights are warranted at this time. ...Southern Cascades... Some potential for thunderstorm activity exists Saturday evening across portions of the Oregon Cascades. However, precipitable water content at or exceeding 1 inch, slow storm motions, low buoyancy, and meager fuels will limit the overall threat of lightning-based ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...Columbia Basin... Increasing west/southwest flow aloft ahead of the next Pacific Northwest mid-level trough as well as an increasing onshore pressure gradient will promote enhanced downslope winds leeward of the Cascades and into the Columbia Basin Saturday. Breezy winds of 10-15 mph (localized Cascade gap winds of 20 mph) and relative humidity as low as 10% amid dry fuels will support an elevated fire weather threat for the Columbia Basin. No significant changes were made to the existing Elevated highlight area. ..Williams.. 09/19/2025 .PREV DISCUSSION... /ISSUED 0127 AM CDT Fri Sep 19 2025/ ...Synopsis... Elevated fire-weather conditions are forecast across portions of the northern Cascades as a mid-level trough approaches the Pacific Northwest. Otherwise, generally weak surface winds across the U.S. and higher precipitable water content where convection is expected will diminish any widespread fire-weather concerns. ...Northern Cascades... Ridging and an intensifying height gradient aloft from an approaching mid-level trough will result in some downslope westerly surface winds through the Cascade gaps. These winds are expected to reach 15-20 MPH, with relative humidity values as low as 10-15%. With ERCs hovering around the 80th annual percentile, and some additional curing of fuels expected on Friday, at least Elevated fire-weather highlights are warranted at this time. ...Southern Cascades... Some potential for thunderstorm activity exists Saturday evening across portions of the Oregon Cascades. However, precipitable water content at or exceeding 1 inch, slow storm motions, low buoyancy, and meager fuels will limit the overall threat of lightning-based ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...Columbia Basin... Increasing west/southwest flow aloft ahead of the next Pacific Northwest mid-level trough as well as an increasing onshore pressure gradient will promote enhanced downslope winds leeward of the Cascades and into the Columbia Basin Saturday. Breezy winds of 10-15 mph (localized Cascade gap winds of 20 mph) and relative humidity as low as 10% amid dry fuels will support an elevated fire weather threat for the Columbia Basin. No significant changes were made to the existing Elevated highlight area. ..Williams.. 09/19/2025 .PREV DISCUSSION... /ISSUED 0127 AM CDT Fri Sep 19 2025/ ...Synopsis... Elevated fire-weather conditions are forecast across portions of the northern Cascades as a mid-level trough approaches the Pacific Northwest. Otherwise, generally weak surface winds across the U.S. and higher precipitable water content where convection is expected will diminish any widespread fire-weather concerns. ...Northern Cascades... Ridging and an intensifying height gradient aloft from an approaching mid-level trough will result in some downslope westerly surface winds through the Cascade gaps. These winds are expected to reach 15-20 MPH, with relative humidity values as low as 10-15%. With ERCs hovering around the 80th annual percentile, and some additional curing of fuels expected on Friday, at least Elevated fire-weather highlights are warranted at this time. ...Southern Cascades... Some potential for thunderstorm activity exists Saturday evening across portions of the Oregon Cascades. However, precipitable water content at or exceeding 1 inch, slow storm motions, low buoyancy, and meager fuels will limit the overall threat of lightning-based ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...Columbia Basin... Increasing west/southwest flow aloft ahead of the next Pacific Northwest mid-level trough as well as an increasing onshore pressure gradient will promote enhanced downslope winds leeward of the Cascades and into the Columbia Basin Saturday. Breezy winds of 10-15 mph (localized Cascade gap winds of 20 mph) and relative humidity as low as 10% amid dry fuels will support an elevated fire weather threat for the Columbia Basin. No significant changes were made to the existing Elevated highlight area. ..Williams.. 09/19/2025 .PREV DISCUSSION... /ISSUED 0127 AM CDT Fri Sep 19 2025/ ...Synopsis... Elevated fire-weather conditions are forecast across portions of the northern Cascades as a mid-level trough approaches the Pacific Northwest. Otherwise, generally weak surface winds across the U.S. and higher precipitable water content where convection is expected will diminish any widespread fire-weather concerns. ...Northern Cascades... Ridging and an intensifying height gradient aloft from an approaching mid-level trough will result in some downslope westerly surface winds through the Cascade gaps. These winds are expected to reach 15-20 MPH, with relative humidity values as low as 10-15%. With ERCs hovering around the 80th annual percentile, and some additional curing of fuels expected on Friday, at least Elevated fire-weather highlights are warranted at this time. ...Southern Cascades... Some potential for thunderstorm activity exists Saturday evening across portions of the Oregon Cascades. However, precipitable water content at or exceeding 1 inch, slow storm motions, low buoyancy, and meager fuels will limit the overall threat of lightning-based ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...Columbia Basin... Increasing west/southwest flow aloft ahead of the next Pacific Northwest mid-level trough as well as an increasing onshore pressure gradient will promote enhanced downslope winds leeward of the Cascades and into the Columbia Basin Saturday. Breezy winds of 10-15 mph (localized Cascade gap winds of 20 mph) and relative humidity as low as 10% amid dry fuels will support an elevated fire weather threat for the Columbia Basin. No significant changes were made to the existing Elevated highlight area. ..Williams.. 09/19/2025 .PREV DISCUSSION... /ISSUED 0127 AM CDT Fri Sep 19 2025/ ...Synopsis... Elevated fire-weather conditions are forecast across portions of the northern Cascades as a mid-level trough approaches the Pacific Northwest. Otherwise, generally weak surface winds across the U.S. and higher precipitable water content where convection is expected will diminish any widespread fire-weather concerns. ...Northern Cascades... Ridging and an intensifying height gradient aloft from an approaching mid-level trough will result in some downslope westerly surface winds through the Cascade gaps. These winds are expected to reach 15-20 MPH, with relative humidity values as low as 10-15%. With ERCs hovering around the 80th annual percentile, and some additional curing of fuels expected on Friday, at least Elevated fire-weather highlights are warranted at this time. ...Southern Cascades... Some potential for thunderstorm activity exists Saturday evening across portions of the Oregon Cascades. However, precipitable water content at or exceeding 1 inch, slow storm motions, low buoyancy, and meager fuels will limit the overall threat of lightning-based ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Sep 19 2025 Valid 201200Z - 211200Z ...Columbia Basin... Increasing west/southwest flow aloft ahead of the next Pacific Northwest mid-level trough as well as an increasing onshore pressure gradient will promote enhanced downslope winds leeward of the Cascades and into the Columbia Basin Saturday. Breezy winds of 10-15 mph (localized Cascade gap winds of 20 mph) and relative humidity as low as 10% amid dry fuels will support an elevated fire weather threat for the Columbia Basin. No significant changes were made to the existing Elevated highlight area. ..Williams.. 09/19/2025 .PREV DISCUSSION... /ISSUED 0127 AM CDT Fri Sep 19 2025/ ...Synopsis... Elevated fire-weather conditions are forecast across portions of the northern Cascades as a mid-level trough approaches the Pacific Northwest. Otherwise, generally weak surface winds across the U.S. and higher precipitable water content where convection is expected will diminish any widespread fire-weather concerns. ...Northern Cascades... Ridging and an intensifying height gradient aloft from an approaching mid-level trough will result in some downslope westerly surface winds through the Cascade gaps. These winds are expected to reach 15-20 MPH, with relative humidity values as low as 10-15%. With ERCs hovering around the 80th annual percentile, and some additional curing of fuels expected on Friday, at least Elevated fire-weather highlights are warranted at this time. ...Southern Cascades... Some potential for thunderstorm activity exists Saturday evening across portions of the Oregon Cascades. However, precipitable water content at or exceeding 1 inch, slow storm motions, low buoyancy, and meager fuels will limit the overall threat of lightning-based ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No Mesoscale Discussions are in effect as of Fri Sep 19 19:55:02 UTC 2025.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Fri Sep 19 2025 Valid 192000Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR SOUTHERN NEBRASKA INTO NORTHWEST AND CENTRAL KANSAS... ...SUMMARY... Isolated severe thunderstorms may impact parts of far southern Nebraska into northwestern and central Kansas late this afternoon and evening, accompanied by some risk for severe hail and wind. ...20z Update... The previous forecast largely remains on track. Latest GOES imagery shows initial thunderstorm development along a weak front across far northwest KS. Ahead of this boundary, modest moisture return across western KS has yielded dewpoints in the upper 50s to low 60s with MLCAPE values increasing to around 1000 J/kg. With temperatures warming into the low 80s, MLCIN is gradually being removed as the front impinges on the returning moisture. Regional VWPs continue to sample 35-40 knot flow at around 4 km AGL, which will support adequate deep-layer shear for organized convection as thunderstorms continue to develop through late afternoon/early evening. Strong/severe thunderstorm coverage remains uncertain with southeastward extent into central KS, but latest observational trends suggest that the severe threat should be relatively greatest across northwest KS through early evening (that said, expected coverage/intensity should remain sufficiently limited to maintain Marginal risk highlights). Elsewhere, the previous forecast (below) remains on track. Instances of sporadic hail and/or wind damage will be possible from eastern AR into northern MS and northwest AL through early evening; however, the convective environment is favorable for mainly short-lived pulse convection (per observed radar trends and regional VWPs), making predictability of any substantial severe threat very limited. ..Moore.. 09/19/2025 .PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Sep 19 2025/ ...Central Plains... Increasing large-scale ascent associated with the embedded shortwave trough and modestly enhanced west-northwesterly jet should influence isolated thunderstorm development by late afternoon/early evening across parts of southwest Nebraska into western Kansas. This region should have a modestly moist low-level airmass in place, with enough daytime heating forecast to support around 1000-1500 J/kg of MLCAPE. Even though mid-level lapse rates are not expected to become overly steep, strong deep-layer shear should aid in convective updraft organization. Any thunderstorms that can form and be sustained could produce isolated severe hail and/or wind gusts as they spread southeastward across western/central Kansas through the evening. ...Midwest/Mississippi Valley... An eastward-moving shortwave trough over the Upper Midwest will more directly influence the middle/upper Mississippi Valley, with moderate destabilization expected this afternoon from the middle Mississippi Valley southward into the Mid-South where MLCAPE will tend to reach 1500-2000 J/kg. Weak deep tropospheric winds will be prevalent along with weak mid-level lapse rates. Even so, some strong to locally severe pulse storms may occur this afternoon through early evening in a broad region spanning parts of Wisconsin/Illinois southward to the Mid-South. ...Western/south-central Minnesota and vicinity... Pending cloud breaks/sufficient heating, scenario may be conducive for funnels and possibly a low chance of a brief tornado in proximity to the upper low and residual surface front, where low-level CAPE/ambient vorticity will be maximized. It is a generally similar regime as to yesterday's reported brief tornado in far southeast North Dakota, although today's setup may be less supportive and more uncertain. ...Southwest States including southeast Arizona... Showers and thunderstorms are ongoing early today across parts of central/eastern Arizona, and on a more isolated basis into western New Mexico and far west Texas. This activity is related to weak ascent aloft associated with minor perturbations rotating through/around a weak upper ridge over the Southwest. Some guidance shows potential for additional robust thunderstorm development by late afternoon/early evening, likely aided by orographic lift and other weak mid-level disturbances. While a localized severe storm or two could occur, substantial uncertainty exists regarding the intensity of these thunderstorms later today owing to ongoing clouds/precipitation, lack of a notable EML, and limited forecast instability. Read more